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问题 填空题

z=f(u，x，y)，x2=x2ey，其中f具有连续的二阶偏导数，则

答案

参考答案：2xeyf’1+2x3f"11+2xeyf"13+x2eyf"21+f"23

解析： [*]

单项选择题 A1型题

诊断风湿热，具有下列各项表现，除了（）

A.心脏炎

B.多发性关节炎

C.环形红斑

D.发热

E.皮下小结节
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单项选择题

In the dining room of my grandfather’ s house stood his heavy clock. Meals in the dining room were a (21) for our four generations to become one. My grandfather’ s clock always stood like a trusted old family friend, (22) us playing jokes and tellingstories, which was already a (23) of our life.

When I was a child, the old clock interested me. I watched and listened to it during (24) I was surprised how at (25) times of the day, the clock would strike three times, six times or more, with a wonderful great (26) that echoed throughout the house. The clock chimed year after year, a part of my (27) , a part of my heart.

Even more (28) to me was my grandfather’s special action each day. He meticulously (29) the clock with a special key each day. The key was magic to me. It (30) our family’ s magnificent clock ticking and striking all year round.

30（）

A.shock 

B.sound 

C.song 

D.music
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